1. Field of the Invention
The present invention relates to a cosmetic container for receiving a stick-like cosmetic such as a lipstick, which can smoothly extract and retract a stick-like cosmetic such as a lipstick accommodated therein.
2. Description of the Prior Art
As a main body of a conventional cosmetic container, a cylindrical body formed by pressing a flat plate, namely a so-called pressing pipe, has been used. However, a great number of steps are required for manufacturing the pressing pipe, and it is difficult to make the cylindrical body to have a cross-section of a complete circle. Therefore, in order to reduce the number of the manufacturing steps, to improve dimensional precision of the main body, and to smoothen extraction and retraction of the cosmetic relative to the container, it has become the recent practice that a straight pipe formed by drawing is used as the main body.
FIG. 31 shows an example of a prior art cosmetic container using a straight pipe as a main body.
As shown in FIG. 31, within a decorative casing 200 having an upper open end, a main body 201 composed of a straight pipe formed by drawing is arranged co-axially and relatively rotatably therewith. There is a space between the casing 200 and the main body 201. A cylindrical outer body 205 provided with a continuous spiral groove 207 on an inner peripheral surface thereof is arranged between the casing 200 and the main body 201. The outer body 205 is integrally fitted to the bore of the casing 200. An insert sleeve 203 is permanently fitted to the upper end portion of the outer body 205 to rotatably surround the main body 201. Within the main body 201, a cosmetic holder 209 for receiving and holding a cosmetic is received. Diametrical projections 211, 211 opposed to each other are provided at the lower end portion of the holder 209. These projections 211, 211 pass through elongated slots 213, 213 provided in the lower portion of the main body 201 to engage with the spiral groove 207. On the outer periphery of the center portion of the main body 201 is formed a projecting bead 215 which is engaged with an internal recess 206 of the outer body 205 to prevent removal or separation of the main body 201. Reference numeral 216 indicates a cap for detachably closing the upper open end of the casing 200.
In use, by rotating an integral assembly comprising the casing 200, the outer body 205 and the insert sleeve 203, the projections 211, 211 in engagement with the spiral groove 207 are guided along the slots 213, 213 of the main body 201 to move up and down, to achieve extraction and retraction of the cosmetic holder 209.
In such a conventional cosmetic container, the outer body 205 is in contact with the main body 201, and the insert sleeve 203 is in contact with the outer body 205 and the main body 201, respectively.
However, a straight pipe manufactured by drawing will inevitably have a certain degree of diametrical dimensional error. The extraction and retraction property of the cosmetic container is greatly governed by frictional resistance between the main body 201 and the outer body 205, especially at the abutment portion at which the bead 215 is engaged within the recess 206. The frictional resistance would, in turn, vary depending upon dimensional relationship between the main 201, the outer body 205 and the insert sleeve 203.
For example, when the diameter of the insert sleeve 203 is relatively small, an excessive degree of frictional resistance may exist between the main body 201 and the outer body 205, and the cosmetic holder 209 can not be moved smoothly.
When a diameter of the insert sleeve 203 is relatively large, the frictional resistance between the main body 201 and the outer body 205 in the abutment portion is decreased. In this case, the cosmetic holder 209 can be moved too easily, and a user would have difficulty in using the cosmetic. Further, airtightness of the container is degraded, and there is a possibility of deteriorating the cosmetic by an invasion of the open air.
In another prior art, a lubricant such as silicon grease is applied to the contacts between the respective constituents of the container in order to smoothen extraction and retraction of the cosmetic. However, use of silicon grease is not desirable, because the cosmetic tends to deteriorate under the influence of components of the silicon grease during the long-term use.
It is lately in fashion to use a cosmetic hard to melt away, a moist cosmetic, etc. However, cosmetic of such a type has a relatively large content of a volatile substance. Therefore, unless the container provides a good airtightness, the cosmetic would be deteriorated. Further, when the airtightness of the container is not excellent, after the cosmetic is accommodated, so-called "slip-out" (a phenomenon that the cosmetic is contracted and consequently slipped out of the cosmetic holder); "desertion" (a phenomenon that the cosmetic cannot effectively cope with movement of the cosmetic holder); and "breakage" (a phenomenon that the cosmetic is contracted and consequently becomes easy to break). In order to prevent such phenomena, airtightness of the container becomes a critical requirement.